Bad breath is the most common effect noted by owners. However, this is often only the tip of the iceberg. The gums become irritated, leading to bleeding and oral pain, and your cat or dog may lose its appetite or drop food from its mouth while eating. The roots may become so severely affected that some teeth become loose and fall out. Bacteria surrounding the roots gain access to the blood stream ("bacteremia"). Studies have shown that dogs with severe periodontal disease have more severe microscopic damage in their kidneys, heart muscle
and liver than do dogs with less severe periodontal disease.